Input text into your arduino code using 5 key keyboard`

1// Mario's Ideas
2// Text input using OLED display an 5 Key Keyboard
3
4#include  <SPI.h>
5#include <Wire.h>
6#include <Adafruit_GFX.h>
7#include <Adafruit_SSD1306.h>
8
9//  Oled display size
10#define SCREEN_WIDTH 128 // OLED display width, in pixels
11#define  SCREEN_HEIGHT 64 // OLED display height, in pixels
12
13//Potentiometer PIN A1
14  int Keyboard=A7;
15
16// Variables capturing current and newly calculated position  on the letter board (9x3 - 27 postions)
17  int New_X=0;
18  int Old_X=0;
19  int New_Y=0;
20  int Old_Y=0;
21  
22// Variable capturing output from Keyboard  pin (Values 0 1023)
23  int Key_read=0;
24  int Prev_Key_read=1023;
25  boolean  Key_pressed=false; 
26
27// String variable holding the text to transmit
28  String  To_Transmit="";
29
30// Length of the text to transmit
31  int To_Transmit_Length=0;
32
33
34//  Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
35  #define  OLED_RESET     4 // Reset pin # (or -1 if sharing Arduino reset pin)
36  Adafruit_SSD1306  display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
37
38
39// Used for  displaying Leter board
40char Letters[3][9]={"ABCDEFGHI",
41                    "JKLMNOPQR",
42                    "STUVWXYZ_"};
43
44
45
46
47void setup() {
48  Serial.begin(9600);
49  
50  // SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally
51  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
52    Serial.println(F("SSD1306 allocation failed"));
53    for(;;); // Don't proceed,  loop forever
54  }
55
56  // Show initial display buffer contents on the screen  --
57  // the library initializes this with an Adafruit splash screen.
58  display.display();
59  delay(2000); // Pause for 2 seconds
60  
61  // Clear the buffer
62  display.clearDisplay();
63  display.display();
64  
65  // Display filled in rect in the top section of  the display when To_Transfer would be output
66  display.fillRect(0, 0, 128, 15,  SSD1306_INVERSE);
67  display.drawRect(110, 2, 16, 12, SSD1306_BLACK);
68  display.setTextSize(1);            
69  display.setTextColor(SSD1306_BLACK);  
70  display.setCursor(113,4);  
71  display.println("OK");
72  display.display();
73  // Display Letter Board  3 rows 9 character in each row 
74  display.setTextSize(2);            
75  display.setTextColor(SSD1306_WHITE);       
76  for (int j=0; j<3;j++){
77    for (int i=0; i<9;i++){
78       display.setCursor(i*12+2*i+1,j*16+17);           
79       display.println(Letters[j][i]);
80       delay(10);
81     display.display();
82    }
83  }
84
85  // Highlight character A by displaying Inverse rect at first  position
86  display.fillRect(0, 16, 12, 16, SSD1306_INVERSE);
87  display.display();
88  
89}
90
91void Highlight_letter(int X, int X_Old, int Y, int Y_Old){
92  //  When position changes 
93  // Draw the inverse rect in the Old_pos to deactivate  the highlight in the old spot
94  // Draw the inverse rect to Highlite the new  spot
95
96  // Displaying Inverse rect in a new position to highlight
97  display.fillRect(X*12+2*X,  Y*16 +16, 12, 16, SSD1306_INVERSE);
98  
99  // Displaying Inverse rect in the  old positon to unhighlight
100  display.fillRect(X_Old*12+2*X_Old, Y_Old*16 +16,  12, 16, SSD1306_INVERSE);
101  
102  display.display();
103}
104
105
106void loop()  {
107  Key_read =analogRead(Keyboard);
108  if (Prev_Key_read>1000 and Key_read<1000){
109    Key_pressed=true;
110    if (Key_read<10 and Old_X>0) New_X=Old_X-1; 
111    if  (Key_read>160 and Key_read<170 and Old_X<9) New_X=Old_X+1;
112    if (Key_read>25  and Key_read<35 and Old_Y>-1) New_Y=Old_Y-1;
113    if (Key_read>80 and Key_read<90  and  Old_Y<2 ) New_Y=Old_Y+1;
114    if (Key_read>350 and Key_read<360) {
115     if  (New_Y!=-1){
116       To_Transmit=To_Transmit + Letters[New_Y][New_X];
117       To_Transmit_Length++;
118       display.setTextSize(1);
119       display.setCursor(3,1);
120       display.setTextColor(BLACK     );
121       display.fillRect(0, 0, 100, 15, SSD1306_WHITE);
122       display.println(To_Transmit);
123       display.display();
124     }
125     else{
126      for (int i=1;i<9;i++)  {
127        display.fillRect(0, 0, 128, 15, SSD1306_INVERSE);
128        delay(300);
129        display.display();
130      }
131     }
132    }     
133
134    if (New_Y==-1  and Old_Y==0){
135        display.fillRect(110, 2, 16, 12, SSD1306_INVERSE); 
136        display.fillRect(Old_X*12+2*Old_X, Old_Y*16 +16, 12, 16, SSD1306_INVERSE);  
137    }
138    if (New_Y==0 and Old_Y==-1){
139        display.fillRect(110, 2,  16, 12, SSD1306_INVERSE); 
140        display.fillRect(New_X*12+2*New_X, New_Y*16  +16, 12, 16, SSD1306_INVERSE);
141        Prev_Key_read=Key_read;
142        Old_X=New_X;
143        Old_Y=New_Y;;
144    }
145    if ((Old_X!=New_X or Old_Y!=New_Y) and Old_Y!=-1  ){
146        if (New_Y!=-1 )Highlight_letter (New_X,Old_X,New_Y,Old_Y);
147        Old_X=New_X;
148        Old_Y=New_Y;
149    }
150  }
151  
152  display.display();
153  Prev_Key_read=Key_read;  
154      
155}